*The reason you don't see ash content published on bags any more in the US is that the pet food regulatory body AAFCO does not allow it. The reason for this is that years ago, a study was conducted that proved ash content was not a contributing factor in Urinary Tract Disease associated with the development of crystals or stones. In this study, they fed a very high ash content diet, but changed the Ph and proved it prevented the most common type of urinary crystal from forming. Based on this study, the dry cat food industry moved immediately to adjust the Ph in their foods. However, while changing the Ph reduced the incidence of one type of stone, it increased the incidence of another type of stone. Both calcium struvite and calcium oxolate stones form in opposite Ph environments. So how can we prevent urinary tract stones from forming?

The belief today by most dry food companies is that controlling the levels of magnesium in diets can help prevent urinary tract crystals. While this is true to a certain extent, you really have to look at the nature of cats in general to get a clue to what is going on with respect to crystal formation. Unlike dogs, cats never did develop a strong drink reflex. All house cats can be traced back to as few as five North African Wildcats that lived about 10,000 years ago. In addition to being home to the Great Pyramids, North Africa is the most arid region on earth. This area encompasses the Sahara Desert. Cats in this region relied primarily on moisture from prey, not free standing water for hydration. For this reason, most cats that eat dry food are dehydrated. While there is also a genetic component to the development of urinary tract stones, the best thing you can do for your cat is to feed him food that is about 70% water just like prey. This forces a higher level of hydration which helps prevents crystals from forming (think about how you make rock candy - more water and less sugar and no crystals will form).

Take a look at the ash numbers when DNA is rehydrated. We have been feeding extruded dy food for so long that we assume that is what cats should eat. However, most of the "rules" we have had to learn about feeding dry food simply do not exist in nature. This is why DNA recommends that you rehydrate your cat's food for better urinary tract health.